1. Field of the Invention
The present invention relates to an information processing device such as a facsimile device, a personal computer, or a peripheral device connected to a personal computer.
2. Description of the Related Art
Recently, many personal computers are provided with central processing units or processors capable of concurrently processing multi-task functions, that is, tasks of a plurality of jobs using time sharing processes. Such a personal computer is convenient because it can simultaneously execute two different programs concurrently. For example, the personal computer can execute a program to drive a printer in order to print out image data onto a recording sheet and, at the same time, drive a scanner to retrieve an image of a desired document.
Such a personal computer can be connected with a printer to print out desired images on a variety of different sizes of recording sheets. In this situation, it is necessary for a user to set a variety of settings, such as print direction and size of the print sheets to be used in the printer. However, if the user accidentally or intentionally operates the printer switch before completing the printer settings, then the printer will be driven to perhaps print image data under printing conditions not desired by the user. For example, print data can be printed on an inappropriate size sheet or in an inappropriate font.
Also, while the personal computer having a multi-task function is processing a task of a first job, which requires a certain resource, then sometimes it is inappropriate to interrupt the first task to perform a second task of another job when the second task of the other job requires the same resource. Conventionally, programs for executing multi-task processes have been designed to prevent such problems from occurring. However, these programs are extremely complicated and require a great deal of time and money to produce.
The above-described problems are not limited to personal computers having a multi-task function, but are also relevant to other information processing devices, such as facsimile devices including data processing units, such as CPUs having multi-task function capability.
It is an objective of the present invention to overcome the above-described problems and to provide an information processing device capable of, when a plurality of jobs inappropriate for being concurrently processed are to be processed, preventing, using a simple means, tasks of the plurality of jobs from being processed concurrently.
In order to achieve the above-described objectives, an information processing device according to the present invention is capable of concurrently processing tasks of a plurality of jobs using time sharing methods and includes a job determination unit that determines when a first job is to be executed; and a data processing unit that, when the job determination unit determines that the first job is to be executed, performs data processes to indicate that a resource, which is the subject of a conflict between the first job and a second job, is presently being used.
With this configuration, when the data processing unit is executing the task of the first job, then it performs data processes indicating that the resource common to both the first job and the second job is being used. Therefore, even if the data processing unit receives a command to execute the task of the second job while the data processing unit is executing the task of the first job, the data processing unit will not be able to secure the resource common to both tasks of the first and the second job. In other words, tasks of the second job will be impossible to execute. Therefore, there is no fear that the data processing unit will attempt to concurrently process the first job and the second job, which both compete for the same resource. This is accomplished simply in the present invention by simple data processes by the data processing unit to indicate that the resource common to both the first and the second jobs is being used. Also, the program for executing these data processes has a simple content so that the processors can be easily and inexpensively produced.
According to another aspect of the present invention, the first job is a printer setting job for setting the drive condition of the printer and the second job is a printing job for printing images using the printer. Because the data processing unit will be unable to secure the printer for performing a printing operation, even when it receives a command to execute a printing job while the printer setting job is being performed, the data processing unit will not performed the printing job during the middle of the printer setting job.
According to another aspect of the present invention, the first job is for performing a facsimile transmission or reception using a modern and the second job is either a scanner job for driving the scanner or a printer job for driving the printer. Even if the data processing unit receives a command for a job that requires the scanner while executing a facsimile transmission job, the data processing unit will be unable to secure the scanner and so will not perform the job requiring the scanner. Similarly, even if the data processing unit receives a command for a job that requires the printer while executing a facsimile reception job, the data processing unit will be unable to secure the printer and so will not perform the job requiring the printer. In this way, facsimile transmissions and receptions can be smoothly performed.